Multi mode filter for realizing wide band using capacitive coupling / inductive coupling and capable of tuning coupling value

Abstract

A multi-mode filter for realizing wide band using capacitive coupling and inductive coupling and capable of tuning coupling value is disclosed. The multi-mode filter includes a housing; a first cavity and a second cavity formed in the housing; a first resonator located in the first cavity, a second resonator located in the second cavity, a wall configured to separate the first cavity from the second cavity; and a first coupling element, wherein a groove is formed between the housing and the wall, the first coupling element is inserted in the groove in crossing direction to the wall, one part of the first coupling element is disposed in the first cavity, another part of the first coupling element is disposed in the second cavity, and the first coupling element is connected to a ground.

The invention claimed is: 
     
       1. A multi-mode filter comprising:
 a housing; 
 a first cavity and a second cavity formed in the housing; 
 a first resonator located in the first cavity; 
 a second resonator located in the second cavity; 
 a wall configured to separate the first cavity from the second cavity; and 
 a first coupling element, 
 wherein a groove is formed between the housing and the wall, the first coupling element is located in the groove in the direction crossing over the wall, a part of the first coupling element is disposed in the first cavity, another part of the first coupling element is disposed in the second cavity, the first coupling element is electrically connected to a ground, and the first coupling element performs electrical coupling between the first resonator and the second resonator using both E-field coupling and H-field coupling. 
 
     
     
       2. The multi-mode filter of  claim 1 , wherein the first coupling element has “ ” shape. 
     
     
       3. The multi-mode filter of  claim 2 , wherein the first coupling element “ ” shape is defined by,
 a first coupling member inserted in the groove; 
 a second coupling member longitudinal-extended from the first coupling member in the direction vertical to the first coupling member, the second coupling member being disposed in the first cavity; 
 a third coupling member longitudinal-extended from the first coupling member in the direction vertical to the first coupling member, the third coupling member locating in the second cavity; 
 a fourth coupling member longitudinal-extended from the second coupling member in the direction vertical to the second coupling member, the fourth coupling member being connected electrically to a bottom surface of the housing corresponding to the first cavity; and 
 a fifth coupling member longitudinal-extended from the third coupling member in the direction vertical to the third coupling member, the fifth coupling member being connected electrically to the bottom surface of the housing corresponding to the second cavity, 
 wherein the fourth coupling member and the fifth coupling member are connected to the bottom surface of the housing through a metal screw. 
 
     
     
       4. The multi-mode filter of  claim 1 , wherein a coupling window is formed in the middle of the wall, a second coupling element is inserted in the coupling window, one end part of the second coupling element is disposed in the first cavity, the other end part of the second coupling element is disposed in the second cavity. 
     
     
       5. The multi-mode filter of  claim 1 , further comprising:
 at least one tuning element which is located in at least one of the first cavity and the second cavity, and disposed to face the first coupling element. 
 
     
     
       6. The multi-mode filter of  claim 5 , further comprising:
 a cover for covering the housing, 
 wherein a first tuning element of the at least one tuning element is disposed in the first cavity and combined with the cover, a second tuning element of the at least one tuning element is located in the second cavity and combined with the cover, the first tuning element is disposed between the first coupling element and an inner surface of the housing corresponding to the first cavity, the second tuning element is located between the first coupling element and an inner surface of the housing corresponding to the second cavity, and the first tuning element and the second tuning element move up and down when combined with the cover. 
 
     
     
       7. The multi-mode filter of  claim 6 , wherein the first coupling element comprises,
 a first coupling member inserted in the groove; 
 a second coupling member longitudinal-extended from the first coupling member in the direction vertical to the first coupling member, the second coupling member being disposed in the first cavity; 
 a third coupling member longitudinal-extended from the first coupling member in the direction vertical to the first coupling member, the third coupling member being disposed in the second cavity; 
 a fourth coupling member longitudinal-extended from the second coupling member in the direction vertical to the second coupling member, the fourth coupling member being connected electrically to a bottom surface of the housing corresponding to the first cavity; and 
 a fifth coupling member longitudinal-extended from the third coupling member in the direction vertical to the third coupling member, the fifth coupling member being connected electrically to the bottom surface of the housing corresponding to the second cavity, 
 wherein the fourth coupling member and the fifth coupling member are connected to the bottom surface of the housing through a metal screw, the first tuning element is disposed between the second coupling member and an inner surface of the housing corresponding to the first cavity, the second tuning element is disposed between the third coupling member and an inner surface of the housing corresponding to the second cavity. 
 
     
     
       8. A multi-mode filter comprising:
 a housing; 
 a first cavity and a second cavity formed in the housing; 
 a first resonator located in the first cavity; 
 a second resonator located in the second cavity; 
 a wall configured to separate the first cavity from the second cavity; and 
 a coupling element, 
 wherein a groove is formed between the housing and the wall, the coupling element is located in the groove in the direction crossing over the wall, a part of the coupling element is disposed in the first cavity, another part of the coupling element is disposed in the second cavity, and the coupling element is electrically open, and the coupling element couples the first resonator with the second resonator using both E-field coupling and H-field coupling. 
 
     
     
       9. The multi-mode filter of  claim 8 , wherein the coupling element has “ ” shape. 
     
     
       10. The multi-mode filter of  claim 8 , wherein the first coupling element “ ” shape is defined by,
 a first coupling member inserted in the groove; 
 a second coupling member longitudinal-extended from the first coupling member in the direction vertical to the first coupling member, the second coupling member being disposed in the first cavity; 
 a third coupling member longitudinal-extended from the first coupling member in the direction vertical to the first coupling member, the third coupling member being disposed in the second cavity; 
 wherein the second coupling member is disposed between an inner surface of the housing corresponding to the first cavity and the first resonator with separated physically from the inner surface of the housing, the third coupling member is disposed between the inner surface of the housing corresponding to the second cavity and the second resonator with separated physically from the inner surface of the housing corresponding to the second cavity, and the second coupling member and the third coupling member is separated physically from bottom surfaces of the housing corresponding to the first cavity and the second cavity. 
 
     
     
       11. The multi-mode filter of  claim 10 , further comprising:
 a fixing member for fixing the first coupling member to be supported by the housing and the wall. 
 
     
     
       12. The multi-mode filter of  claim 8 , further comprising:
 at least one tuning element which is located in at least one of the first cavity and the second cavity, and disposed to face the first coupling element. 
 
     
     
       13. The multi-mode filter of  claim 12 , further comprising:
 a cover for covering the housing, 
 wherein a first tuning element of the at least one tuning element is disposed in the first cavity and combined with the cover, a second tuning element of the at least on tuning element is disposed in the second cavity and combined with the cover, the first tuning element is disposed between the first coupling element and an inner surface of the housing corresponding to the first cavity, the second tuning element is disposed between the first coupling element and an inner surface of the housing corresponding to the second cavity, and the first tuning element and the second tuning element move up and down when combined with the cover. 
 
     
     
       14. The multi-mode filter of  claim 13 , wherein the first element comprise,
 a first coupling member inserted in the groove; 
 a second coupling member longitudinal-extended from the first coupling member in the direction vertical to the first coupling member, the second coupling member being disposed in the first cavity; 
 a third coupling member longitudinal-extended from the first coupling member in the direction vertical to the first coupling member, the third coupling member being disposed in the second cavity; 
 wherein the second coupling member is disposed between an inner surface of the housing corresponding to the first cavity and the first resonator with separated physically from the inner surface of the housing corresponding to the first cavity, the third coupling member is disposed between the inner surface of the housing corresponding to the second cavity and the second resonator with separated physically from the inner surface of the housing corresponding to the second cavity, the second coupling member and the third coupling member is separated physically from bottom surfaces of the housing corresponding to the first cavity and the second cavity, the first tuning element is disposed between the second coupling member and the inner surface of the housing corresponding to the first cavity, the second tuning element is disposed between the third coupling member and the inner surface of the housing corresponding to the second cavity. 
 
     
     
       15. A multi-mode filter comprising:
 a housing; 
 a first cavity and a second cavity formed in the housing; 
 a first resonator located in the first cavity; 
 a second resonator located in the second cavity; 
 a wall configured to separate the first cavity from the second cavity; 
 a first coupling element; and 
 at least one tuning element, 
 a cover to cover the housing; 
 wherein a groove is formed between the housing and the wall, the first coupling element is inserted in the groove in the direction crossing over the wall, a part of the first coupling element is disposed in the first cavity, another part of the first coupling element is disposed in the second cavity, the at least one tuning element is disposed to face the first coupling element which is located in at least one of the first cavity and the second cavity, the at least one tuning element is combined with the cover and the at least one tuning element moves up and down.